5. Additional notes about TrueType support

This version of XFree86 comes with two TrueType backends,
FreeType (module `freetype', formerly known as xfsft) and
X-TrueType (module `xtt'). These two backends are not
compatible: only one of them can be used at any one time.

In order to use the FreeType backend, please check that the
`Module' section of your `XF86Config' file contains a line
that reads

Load "freetype"

In order to use the X-TrueType backend, replace the line in your
XF86Config file that loads the freetype module with a
line that reads

Load "xtt"

Both TrueType backends delay glyph rasterisation up to the time at
which a glyph is first used. For this reason, they only provide an
approximate value for the ``average width'' font property.

Both backends also support an optimisation for character-cell fonts
(fonts with all glyph metrics equal, or terminal fonts). A font with
an XLFD specifying a character-cell spacing `c', as in

-misc-mincho-medium-r-normal--0-0-0-0-c-0-jisx0208.1990-0

will not rasterise glyphs at metrics computation time, but instead
trust the font really to be a character-cell font. You are
encouraged to make use of this optimisation when useful, but be warned
that not all monospaced fonts are character-cell fonts.

5.1. The FreeType TrueType backend

The FreeType backend (formerly xfsft) is a backend based on
the FreeType library (see the FreeType web site) and has support for the ``fontenc''
style of internationalisation (see Section
The fontenc layer). This backend supports TrueType Font files
(`*.ttf') and TrueType Collections (`*.ttc').

In order to access the faces in a TrueType Collection file, the face
number must be specified in the fonts.dir file before the filename
within colons. For example,

5.2. The X-TrueType TrueType backend

The `X-TrueType' backend is another backend based on the FreeType
library. X-TrueType doesn't use the `fontenc' layer for managing font
encodings, but instead uses its own database of encodings. However,
X-TrueType includes a large number of encodings, and any encoding you
need is likely to be present in X-TrueType.

X-TrueType extends the `fonts.dir' syntax with a number of options,
known as `TTCap'. A `TTCap' entry follows the general syntax

:option=value:

and should be specified before the filename.

The most useful TTCap option is used to specify the face number to use
with TTCs; this is the `fn' TTCap option. For example, face 2 of
font file `mincho.ttc' is specified using: